From the pocket computers we call smartphones, to the booming tablet market, to handheld devices that display 3D imagery without glasses, just about every cutting-edge, consumer-grade technology ends up in mobile devices. Perhaps the biggest issue portables face, though, isn’t the ability to house complicated tech but to simply maintain a charge. However, a team of scientists has developed a portable nanogenerator that is capable of partially charging a lithium-ion battery using ambient energy as a power source.

The team of scientists composed of Sihong Wang, Ya Yang, Yan Zhang, and Zhon Lin Wang, dubbed the device “PENG,” which stands for pyroelectric nanogenerator. PENG gathers thermal energy through the use of the pyroelectric effect, basically how small changes in temperature have electric potential. Essentially, the nanogenerator harvests unused, potential energy from its surroundings and puts it to use.